All of the Numeric data structures returned by the 'self.__getattr__()' function have been shifted
into their own instances of a new objected defined by the DiffAutoNumericObject class. This new
class when instantiated expects as an argument a function which will return a Numeric array, matrix,
etc. Using this function, the object currently implements the functions:
__add__(), implementation of addition.
__getitem__(), selecting individual elements of the array.
__iter__(), for looping over the array.
__len__(), the length of the array.
__mul__(), implementation of multiplication.
__repr__(), the 'official' string representation.
__setitm__(), throw a RelaxError if modification of the structure is attempted.
To enable the automatically generated objects, the code from 'self.__getattr__()' has been shifted
into the following 'hidden' functions of the DiffTensorElement class:
_auto_object_Dpar_unit()
_auto_object_Dx_unit()
_auto_object_Dy_unit()
_auto_object_Dz_unit()
_auto_object_rotation()
_auto_object_tensor()
_auto_object_tensor_diag()
